1. Field of the Invention
The present invention relates to a film transport apparatus such as a microfilm reader and the like, and more particularly to a film transport apparatus for a microfilm reader or microfilm reader/printer which uses a cartridge including a reel on which a rolled film is wound.
2. Related Background Art
As the cartridge which accommodates a rolled film used for the microfilm reader or microfilm reader/printer, a type A cartridge of the ANSI (American National Standards Institute, Inc.) standard and a type M cartridge of 3M (Minnesota Mining & Manufacturing) have been known.
Those cartridges are mounted on a film transport apparatus of the microfilm reader to drive a reel on which the rolled film is wound so that the film is fed out of the cartridge or rewound on the reel of the cartridge.
Since a reel drive method and a method for feeding out a leading edge of the film are different from cartridge to cartridge, a unique film transport apparatus is used for each cartridge. This is inconvenient to users and results in increased costs to of the users.
In order to resolve the above problem, a microfilm reader which is applicable to both types of cartridge has been proposed (for example, Japanese patent application Laid Open No. 63-210832).
In this prior art apparatus, however, since film feed-out machanisms for the two types of cartridge are incorporated, the number of parts is large and construction is complex. As a result, the cost is high and trouble can easily to occur.
FIG. 1 shows the type A cartridge. The cartridge 100 comprises a circular hold unit 102 for holding a reel 101, a bottom opening 103 formed along a film guide path in the cartridge and a film feed-out opening 104. The reel 101 on which a film F is wound is fit into the held unit 102 and rotatably hold thereby.
A film feed-out device of the film transport apparatus for the type A cartridge is shown in FIG. 2.
When the type A cartridge 100 is mounted in place, it is detected by cartridge detection means (not shown), and a film drive roller 105 is pressed to the rolled film F by the detection signal so that a leading end of the film is fed out. Numeral 105a denotes a film separation pawl which separates the leading end of the film fed out by the drive roller 105 into a guide member of a film transport unit.
The film fed out of the cartridge by the drive roller 105 passes through a guide member in a film transport path and is wound around a take-up reel.
When the film is to be wound up, the drive roller 105 and the film separation pawl 105a are away from the film.
A prior art film feed-out device is explained with reference to FIGS. 2 and 3. The film feed-out device has a roller 105 for rotating the rolled film. A roller drive unit for rotating the roller 105 comprises a belt 121, a belt pulley rotated by the belt 121 and a gear integral with a belt pulley (not shown).
On the other hand, a film separation pawl 105a for separating the leading end of the rolled film is provided on the opposite side of the roller 105. The film separation pawl 105a is tapered starting from the roller 105 toward an extention direction is both width and thickness, and at a tip end, it has a thin knife shape. This is because if the tip end of the film separation pawl 105a, that is, a portion which abuts against the film is small, resistance to the film is low and the film is properly handled. Numeral 103b denotes an inner circumference of the cartridge and numeral 104 denotes a film feed-out opening.
In the prior art rolled film feed-out device, however, if the leading end of the film is warped, or if the leading end of the film is bent, the leading end of the film may abuts against the inner circumference 103b of the cartridge or the bottom opening 103 and the leading end is bent or clogged (see FIG. 2).
Where the leading end of the film is bent outward, the film may driven out of a gap between the film feed-out opening end 104a and the roller 105 so that the transport of the rolled film is blocked (see FIG. 3).